Amanda Bynes 'Has Been a Little Lost' in Recent Years: Source

"This DUI was definitely just a serious lapse in judgment," a source tells PEOPLE of the former Nickelodeon star.

"She hit a wall personally and professionally [in 2008] ... I think she's been a little lost since then," the insider says of the actress, who dated Doug Reinhardt in 2009 and was linked to Liam Hemsworth shortly afterward.

But according to the 26-year-old's father, Rick Bynes, his daughter doesn't drink. He tells PEOPLE she was held in jail because "she was upset and very emotional."

And a source tells PEOPLE that Bynes "seemed fine to drive" when she left the Standard Hotel in West Hollywood – where she is a regular and had dinner Thursday night before her arrest. She had alcohol, but "never seemed drunk," the source says.

Bynes then went to Greystone Manor (where she's also a regular), and was arrested after leaving there. Adds the source: "Bynes tried to come back to party [at the Standard] only hours after she was released from her DUI arrest," but she is no longer welcome at the hotel.

Bynes was held overnight at the West Hollywood Sheriff's department's station following her arrest. Though authorities would not comment on her particular case, the sheriff's station website states, "If the offense is alcohol or drug related, the suspect will stay at the sheriff's station until he or she can safely care for himself or herself."

Another source, who calls Bynes "a very sweet girl," says, "[She] was raised in the industry and came up in the industry, so she has kind of a twisted head space in terms of social groups."

Her dad, however, says, "She just chooses not to work, and because of that people go after her."